2018-02-22T06:46:58ZEstimating forest area at the year 1990 by two-phase sampling on historical remotely sensed imagery in Italyhttp://hdl.handle.net/2067/2136
Title: Estimating forest area at the year 1990 by two-phase sampling on historical remotely sensed imagery in Italy
Authors: Corona, Piermaria; Fattorini, Lorenzo; Chirici, Gherardo; Valentini, Riccardo; Marchetti, Marco
Abstract: Forest area in the year 1990 is a fi gure of great
interest under the Kyoto Protocol. This note is devoted to
a scientifi c exercise for the probabilistic ex post assessment
of such a fi gure in Italy. Estimation was performed by twophase
point sampling, which made use of historical remotely
sensed imagery. In the fi rst phase, a sample of 12 089
points was selected according to an unaligned systematic
sampling and the selected points were classifi ed in land-use
categories by Landsat 5 TM imagery. In the second phase,
a sample of 3000 points was selected by stratifi ed sampling
in which the strata were determined by the satellite classifi
cation and the selected points were classifi ed by aerial
photos, assumed as ground truth. A two-phase estimate of
land-use coverage partitioning the Italian territory was
obtained together with a conservative estimate of the
sampling variance-covariance. The procedure has proved
to be of relatively easy implementation and objective
repeatability
Description: L'articolo è disponibile sul sito dell'editore http://www.springerlink.com/2006-12-31T23:00:00ZComparison of approaches for reporting forest fire-related biomass loss and greenhouse gas emissions in southern Europehttp://hdl.handle.net/2067/2359
Title: Comparison of approaches for reporting forest fire-related biomass loss and greenhouse gas emissions in southern Europe
Authors: Chiriacò, Maria Vincenza; Perugini, Lucia; Cimini, Dora; D'Amato, Enrico; Valentini, Riccardo; Bovio, Giovanni; Corona, Piermaria; Barbati, Anna
Abstract: Wildfires are the most common disturbances in Mediterranean forest ecosystems that cause significant
emissions of greenhouse gases as a result of biomass burning. Despite this, there is reasonably high uncertainty regarding
the actual fraction of burnt biomass and the related CO2 and non-CO2 gas emissions released during forest fires. The aim of
this paper is to compare existing methodologies adopted in the National Greenhouse Gas Inventory reports of five of the
most fire-affected countries of southern Europe (Italy, Spain, Greece, Portugal, France) with those proposed in the
literature, to operationally estimate forest fire emissions, and to discuss current perspectives on reducing uncertainties in
reporting activities for the Land Use, Land Use Change and Forestry sector under the United Nations Framework
Convention on Climate Change and the Kyoto Protocol. Five selected approaches have been experimentally applied for the
estimation of burnt biomass in forest fire events that occurred in Italy in the period 2008–2010. Approaches based on
nominal rates of biomass loss can lead to an overly conservative value or, conversely, to underestimation of the fraction of
burnt biomass. Uncertainties can be greatly reduced by an operational method able to assess inter-annual and local
variability of fire effects on fire-affected forest types.
Description: L'articolo è disponibile sul sito dell'editore http://www.publish.csiro.au2012-12-31T23:00:00ZCambiamenti di copertura forestale e dell’uso del suolo nell’inventario dell’uso delle terre in Italiahttp://hdl.handle.net/2067/2311
Title: Cambiamenti di copertura forestale e dell’uso del suolo nell’inventario dell’uso delle terre in Italia
Authors: Marchetti, Marco; Bertani, Remo; Corona, Piermaria; Valentini, Riccardo
Abstract: Changes of forest coverage and land uses as assessed by the inventory of land uses in Italy. The paper presents
the IUTI program, a land use inventory of Italy, based on point sampling. It has been carried out to
support the National Carbon Sink Accounting Register and it was realized within the framework of the Italian
National Remote Sensing Plan managed by the Italian Ministry of Environment. IUTI has monitored the
land use and land use change and forestry in the last two decades over the country at the years 1990, 2000,
2008, adopting a tessellated stratified sampling scheme with about 1.2 million sample points on aerial orthophotos.
Following definitions, methods and inventory procedures, the main results are discussed. They
show the heavy changes affecting surface and distribution of the various classes for arable lands, forests and
urban areas.
Description: L'articolo è disponibile sul sito dell'editore www.sisef.it2011-12-31T23:00:00ZExtending large-scale forest inventories to assess urban forestshttp://hdl.handle.net/2067/2316
Title: Extending large-scale forest inventories to assess urban forests
Authors: Corona, Piermaria; Agrimi, Mariagrazia; Baffetta, Federica; Barbati, Anna; Chiriacò, Maria Vincenza; Fattorini, Lorenzo; Pompei, Enrico; Valentini, Riccardo; Mattioli, Walter
Abstract: Urban areas are continuously expanding
today, extending their influence on an increasingly
large proportion of woods and trees located
in or nearby urban and urbanizing areas, the socalled
urban forests. Although these forests have
the potential for significantly improving the quality
the urban environment and the well-being of
the urban population, data to quantify the extent
and characteristics of urban forests are still lacking
or fragmentary on a large scale. In this regard,
an expansion of the domain of multipurpose forest
inventories like National Forest Inventories
(NFIs) towards urban forests would be required.
To this end, it would be convenient to exploit the
same sampling scheme applied in NFIs to assess
the basic features of urban forests. This paper considers
approximately unbiased estimators of abundance
and coverage of urban forests, together with
estimators of the corresponding variances, which
can be achieved from the first phase of most largescale
forest inventories. A simulation study is carried
out in order to check the performance of the
considered estimators under various situations involving
the spatial distribution of the urban forests
over the study area. An application is worked out
on the data from the Italian NFI.
Description: L'articolo è disponibile sul sito dell'editore www.springer.com2011-12-31T23:00:00ZLand use inventory as framework for environmental accounting: an application in Italyhttp://hdl.handle.net/2067/2346
Title: Land use inventory as framework for environmental accounting: an application in Italy
Authors: Corona, Piermaria; Barbati, Anna; Tomao, Antonio; Bertani, Remo; Valentini, Riccardo; Marchetti, Marco; Fattorini, Lorenzo; Perugini, Lucia
Abstract: Land use inventories are sound measures to provide information on the area
occupied by different land use or land cover types and their changes, although
less widespread than traditional mapping; as such, they are distinctively wellestablished
tools for generating statistics on the state and the dynamics of land
use in the European Union. Italy has recently set up a land use inventory system
(IUTI) as a key instrument for accounting removals and emissions of greenhouse
gases (GHG) associated to land use, land use change and forestry (LULUCF)
activities elected by Italy under the Kyoto Protocol. IUTI adopts a statistical
sampling procedure to estimate the area covered by LULUCF land use
categories in Italy, and associated uncertainty estimates. Estimates of land use
have been so far processed for the period 1990-2008 and highlight three interlinked
land use change patterns in Italy: (i) increase in forest land for a total
uptake of 1.7% of the Italian territory; forest cover estimates, with a standard
error of 0.1%, indicate an annual increase of forestland higher over the period
1990-2000 (32 901 ha year-1) than in 2000-2008 (22 857 ha year-1); surprisingly,
also a significant deforestation rate is observed (-7000 ha year-1), due to
forest land conversion mainly into artificial areas; (ii) consumption of arable
land (-4.2% of the Italian territory) primarily due to land uptake by urban areas
and to conversions to permanent crops (mainly orchards and vineyards); (iii)
urban sprawl uptakes 1.6% of the Italian territory in this period, with a total
coverage of settlements reaching 7.1% of total land surface in Italy in 2008.
Overall, land use dynamic results in land uptake by forest land is of the same
magnitude of land uptake by urban areas, but the effects of these processes on
GHG removals (by forest sinks) and emissions (by urban areas) is expected to
be significantly different. In a broader perspective, IUTI methodology, by
providing reliable estimates and well-defined levels of statistical uncertainty
for assessing stocks and flows of land use at national level, can be further implemented
to frame other key questions for sustainable development policies,
like the set up of environmental-economic accounting systems.
Description: L'articolo è disponibile sul sito dell'editore www.sisef.it2011-12-31T23:00:00ZDiscrimination of tropical forest types, dominant species, and mapping of functional guilds by hyperspectral and simulated multispectral Sentinel-2 datahttp://hdl.handle.net/2067/2785
Title: Discrimination of tropical forest types, dominant species, and mapping of functional guilds by hyperspectral and simulated multispectral Sentinel-2 data
Authors: Vaglio Laurin, Gaia; Puletti, Nicola; Hawthorne, William; Liesenberg, Veraldo; Corona, Piermaria; Papale, Dario; Chen, Qi; Valentini, Riccardo
Abstract: To answer new scientific and ecological questions and monitor multiple forest changes, a fine scale characterization
of these ecosystems is needed, and could imply the mapping of specific species, of detailed forest types, and
of functional composition. This characterization can be now provided by the novel Earth Observation tools. This
study aims to contribute to understanding the innovation in forest and ecological research that can be brought in
by advanced remote sensing instruments, and proposes the guild mapping approach as a tool to efficiently monitor the varied tropical forest resources. We evaluated, in tropical Ghanaian forests, the ability of airborne
hyperspectral and simulated multispectral Sentinel-2 data, and derived vegetation indices and textures, to: distinguish
between two different forest types; to discriminate among selected dominant species; and to separate
trees species grouped according to their functional guilds: Pioneer, Non Pioneer Light Demanding, and Shade Bearer. We then produced guild classification maps for each area using hyperspectral data. Our results showed
that with both hyperspectral and simulated Sentinel-2 data these discrimination tasks can be successfully accomplished.
Results also stressed the importance of texture features, especially if using the lower spectral and spatial Sentinel-2 resolution data, and highlighted the important role of the new Sentinel-2 data for ecological monitoring.
Classification results showed a statistically significant improvement in overall accuracy using Support Vector Machine, over Maximum Likelihood approach. We proposed the functional guilds mapping as an innovative
approach to: (i) monitor compositional changes, especially with respect to the effects of global climate change
on forests, and particularly in the tropical biome where the occurrence of hundreds of species prevents mapping activities at species level; (ii) support large-scale forest inventories. The imminent Sentinel-2 data could serve to open the road for the development of new concepts and methods in forestry and ecological research.2015-12-31T23:00:00Z